README.md

truth_tables

Create pretty-printed truth tables and abstract syntax trees from boolean expressions! Installation is as easy as pip install truth_tables.

Example usage:

>>> from truth_tables import TruthTable
>>> my_table = TruthTable('p or q', '~p -> q', 'T and ~T')
>>> print(my_table)
┌───┬───┬────────┬─────────┬──────────┐
│ p │ q │ p or q │ ~p -> q │ T and ~T │
├───┼───┼────────┼─────────┼──────────┤
│ F │ F │   F    │    F    │    F     │
│ F │ T │   T    │    T    │    F     │
│ T │ F │   T    │    T    │    F     │
│ T │ T │   T    │    T    │    F     │
└───┴───┴────────┴─────────┴──────────┘
>>> print(my_table.ast)
Or
├─Variable('p')
╰─Variable('q')

Implies
├─Negate
│ ╰─Variable('p')
╰─Variable('q')

And
├─LiteralTrue
╰─Negate
  ╰─LiteralTrue

>>> my_table = TruthTable('~((p xor (q and ~r) or q) and ~(p <-> r))')
>>> print(my_table)
┌───┬───┬───┬───────────────────────────────────────────┐
│ p | q | r | ~((p xor (q and ~r) or q) and ~(p <-> r)) │
├───┼───┼───┼───────────────────────────────────────────┤
│ F | F | F |                     T                     │
│ F | F | T |                     T                     │
│ F | T | F |                     T                     │
│ F | T | T |                     F                     │
│ T | F | F |                     F                     │
│ T | F | T |                     T                     │
│ T | T | F |                     F                     │
│ T | T | T |                     T                     │
└───┴───┴───┴───────────────────────────────────────────┘

Two truth tables are equal if they have the same variables and the same truth values (not necessarily the same propositions).

>>> TruthTable('p -> q') == TruthTable('~p or q')
True

Notes on the Parser

• The parser will accept symbolic or english names for boolean operators:

  operator	symbolic	english
  Not	~	not
  And	&	and
  Or	|	or
  Implies	->	implies
  Iff	<->	iff
  Xor	^	xor

• Not has greater precendence than And and And has greater precedence than Or, Implies, Iff, and Xor.

• T and F are parsed as boolean literals.

• Other than the english operator names and boolean literals, variable names may be any sequence of word characters that don't start with a digit.